Blast-furnace.



A. J. Momma. BLAST FURNAGE.

APPLIOATIGN FILED SEPT. 25, 19114 1,036,1 37, Patented Aug. 20, 1912.

Z SHEETS-SHEET 1.

A. J. MOXHAM. BLAST FURNACE.

APPLIUATION FILED 51111111.25, 1911.

1,0%,1 3'?. Patented Aug. 20, 1912.

2 SHEETS-SHEET 2.

ICC/Q4,

ARTHUR J. MOXHAM, o i wlmi/111Werrori,y DELAWRE.

'B'LasT-FURNACE.

ToaZZ whom z'tvmay concern.'

Be it known that I, ARTHUR J. M oXHAM,

at subject ofthe King of Great' Britain, re-

siding at Wilmington, county of Newcastle,

and State of Delaware, have invented a new and useful Improvement in Blast-Furnaces,

of 'which the following is a full, clear, and

exact description, reference being had to the accompanying drawings, which form a this dust. This ore is blown out through thek This entails considerable less' as lwelles a gathering of the dust en the downccmer.

boiler surfaces, rand otherwise it .adds to the diiculty and cost of manufacture.

An4 analysis ot the ue dust by sizing will show a large amount capable of passing through a 500 meshzsiev'e, and that Very little of the dust fails to pass through a- 100 mesh sieve. This ore dust is onseqently easily carried by the .blast, particularly' when the increased pressure demanded by a charge of Vall fine ore, is used. Thistlo'ss h asv heretofore .been Vattempted to. -bemet-'Q lst, by reducing the percentage. of tine ore carried-in lthe charge', and therefore the amount of waste: 2nd, by gathering, thev accumulation from the dust catcher and the f lues, and 3rd, subsequently briqueting the material so gathered to put it into proper form for once inorefbeing charged through. the furnace lV hat is. called the vtlue dust consists not onlyot tine ore but of more or y f less other'material 'driven out by the blast together with the ore.v An average content of iron in flue dust is frequently as low as thirtyvper cent. (30C/0),*hence the briquets, which are costly toinake, represent when made a low grade of material.

The object of my invention 1s to' prevent this dust passing into the d owncomer, ac-

'curtail-ating n it, and returning it to the charge.

Speaking generally, I surround the Inner surface ot the blast turnaceabove the charge I kSpeeitcation of Letters Patent.

Patented Aug, 20, 1912.

Application'. med september 25,1911. serial No. 651,065,

i with'electroimagnets. Preferably I use a plurality of' tiers of such magnets.- The finer dust passing up 4with the blastis caught by these 'magnets and collected thereby.

l/Vhen *a sufficient quantity has been 'thus collected, the current Ato the magnets is cut ott," which" denergizes them. The dust Will then tend to fall vertically into thefeharge, and theaccumulated dust will be sufficient vto overcome the blast andv carry the dust in part or in whole into or on the charge.

As stated, I preferably use a `pluralityof tiers of magnets. The reason for-.thisii's that I maydenergize onesetof magnets, allowing the collected dust to fall back into the charge, while the remaining tiers being still energized, will prevent the dust `fromithe charge or any ofthe collected dust being blown vout ofthe f urnacefbythe blast. I can also so' arrangethe electric circuits to the tiers of magnets so that successively the tiers are denergized and all the tiersarc simultaneously denergized when theblast is cut ott or, the same time, w,hen the bell is lifted.

1 will ,new describe 'the embodiment of my inventionshown in the accompanying drawings, andythen'point out 'the invention In the claims. v 'In the drawings: Flgure 1 1s avertical section of a Vblast,fur/nace embodying my mainlandy attachltnts for .opening circuit to magnets whenbla'st is cut ott. Fig-4 is adet a i lv s ectional view of the bell, its lever and the switch, controlling the circuit tothe f magnets; controlled b y said lever.-

a is the blast furnace, o the air pressure jconduit, c the twyers, c2 the downcomer, e Y

the bell.

1s a series ofelectro magnets, protruding throughthe walls of the blast furnace;

the brokenline's (Fig. 2) vshow the'fieldof said magnets.` In'like manner g is another series of magnets protruding through' the wall'of theblast furnace above the' magnets f, and t' isa similar set of electroA magnets above theA electro magnets, g.

z' is arod connecting thebell and lever j having the weightJr` v i "l Yis a'switch point pivotedfato and having its free end connected to lever y' by rod y).

l] is a` bindingpost to which a .Wire 7', lead- When the switch points Z and t are connected this circuit is completed. Asmay be seen, this takes place when the `bell lis elel` vated (which, as is well known, 1s when the4 blast-is cut off), and the points arel separated when the bell is depressed' (which, as is well known, is when the blast 1s on). In-

'terposedbetween the electro magnets f, g and h and Wires o and fw is a switch having' contacts y, z, 1 and 2 from the magnets f,

3, 4r, 5 andG from magnets g, and 7, 8, 9 and 10 from magnets z. y As may be seen, 4if the.`

switch is'successively operated, the current connection to the magnets will be made first to magnets f, thenrto magnets g and finally to magnets L, and the breaking will be conversely. Thus with the three sets of magnets showingV the making and breaking of the current, connection is successive, and moreover at all times at least one`of the 'sets of magnets may be energized, and thus escape of the dust by the blast prevented.

In Fig. 2 I have shown in the full curved lines, connecting the pole pieces 'of the magnets, the accumulation of' the dust` Iny Fig. 3 I haveshown an arrangement whereby the circuit to the magnets is broken 'when the blast is cut oli. In this drawing, 7J is the blast main. In this Fig. 3, 2O `is the plunger maintained in position shown by pressure of the blast within the main. 19 the fulcrum for lever 1S.4 l5 and 16 an ordinaryelectric switch, 1l and 12 representing the wires therefrom. 17, link connecting the ievcr 18 with the switch. The figure as shown shows the switch thrown in, the pres sure operating to force the plunger 2O ulpward to position shown for this purpose. When the blast is eut off the pressure in the blast main falls, consequently plunger 20 dro is and b Y means of link 17 ulls switch i l l p lwhat I claim and desire to protect by Letl5 open and thereby cuts off the current, so

that when the blast ofi', the current is also oft' and vice versa.

From what has been described, the operation is apparent, with the bell elevated and all 'the sets of magnets in circuit. The dust carried oli by the blast is collected and heldy by the magnets. By breaking the circuit to' any one of the sets of magnets, retaining the circuit to the other sets, the accumulated dust will by gravity tend to fall back into the charge, and if the accumulation be sufiicient, the greater portion will so fall. The remaining magnets prevent any escape of the small proportiouof the dust that may tend upward. By a corresponding opera-4 tion with respect to the other sets of magnets their accumulated dust may be removed and carried back to the charge. wWhile fresh magnjetized this can be largely checked or reduced. VPreferably Ithe upper zone is retained by. the magnets.

I am not claiming as my invention the broad idea of collecting metal or even ore dust by means of electro-magnets, but I believe it to be novel with me to providepthe electrotmagnets in the blast furnace to catch the' ore dust which would otherwise be blown out of the furnace and which are' in vertical alinement with the charge so that by gravity, when the magnets are denergized, the dust will fall back into the charge. I also believe it to be novel with me to provide the plurality of tiers of magnets which enables one set to be denergized to discharge its accumulated ore dust, While the other set or sets are still energized and stand guard to prevent any dust being blown out by the air blast, Finally, I believe it to be novel with me to simultaneously discharge the accumulation of all the magnets by deenergizing them when the-blast is cut oft".

Many orcsgitilized in the blast furnace, such as limonites and hematites, are nonmagnetic ores, thence the question may occur as to how my invention is operative in this event. It is a fact, however, that the first 10o effect that occurs when such ores meet the ascending gases in the upper part of the blast furnace in connection with the carbon in the coke,that`the pre .is converted quickly into a magneticfcondition. commences at once and is practically complete in the first ten feet or thereabout, the exact-distance depending upon minor conditions, but many event it isthe first effect of the admission of the ore into the furnace. 110

Having now fully described my invention,

ters Patent is:

1. The improvement for preventing the escape of ore dust in blast furnaces and 115 escape of ore/lustin blast furnaces and re- 12E` turning it tot-he charge,`: comprising i`n. com.- binativn` with the yblast furnace and itsv air supplyand twyers electro magnets the'elds of which act upon theinner portion ofgthe upper pel-t of the blast furnace, a source-of lf3@ The operation cloacas? 'current supply,` electrical .connection between said source of current supply and the electro magnets, anda switch for controlling'saicl circuit.v

3. The improvement" for preventing the esca of orefdust in blast furnaces and' returnmg it to the charge, comprising in combination with the blast furnace and its air, supply and twyers, a plurality of tiers of superposed electro-magnets, the fields of which act upon the inner portion of the upper part of rthel blast furnace, a source ofV current supply, electricall connection be; tween said source of current supply and each tier' of magnets.

1; The improvement for prevent-ing' the escape of ore dust in bla-st furnaces and re turning it to the charge, comprising in combination with the blast furnace and its air supply and twyers, a plurality of tiers of superposed electro magnets, the field of which act upon the inner portion of the upper part of the blast furnace, a source of current supply, electrical connection between said source of current supply and eachA tier of magnets, anda switch controlling the circuit to each of the tiers of magnets.

5. The improvement 'for4 preventing the escape of ore dust in blast furnaces and returning it to the charge,l comprising in combination with the blast furnace'and its air' supply and twyers, a plurality' of tiers ofN superposed (electro-magnets, the fields of which act upon the inner portion ofthe upper part of the blast furnace, a source of current supply to each tier of magnets, and a switch controlling the circuits to all the tiers of magnets, and means to operate said switch to open when the blast is cut-,off and to close when the blast is on.

6. The improvement for preventingv the escape of ore dust in blast-furnaces and returning it to the charge, comprising in combination with the blast furnace audits air supply and twyers, a plurality of tiers of superposed electromagnets, the fields of which act upon the inner portion of the upper part of the blast furnace, a'source of current supply to cach tier of magnets, and

ra switch or switches controlling the circuits to all the tiers of magnets, a bell, means connecting said bell and switches to close said switches when the bell is lifted and open the switches when the bell is depressed.

7. The improvement for preventing the escape of ore dust in blast furnaces and .returning it` to the charge, comprising in com4 bination withtthc blast furnace and its air supply and twyers, a plurality ,of tiers of superposed electro-magnets, the fields of which act upon the inner portion of the upper part of the blast furnace, a source of current supply to cach tier of magnets, and a switch controlling the circuitsI to -e tier of magnets, a bell, means connecting said .bell

andsaid switch to close saidswitch when the bell is lifted and open the switch when the i bell is depressed.l

8. The improvementfor preventing the` escape of ore dust in blast furnaces and returning it to the charge, comprising in com` bination withv ,the blast furnace and its air supply and twyers, electro ,magnets the fields lof which act upon the' inner portion of the upper part of the blast furnace, a source of current supply, electrical connection between said source of current supply controlling said circuit, and means to operate said `switch to open when the blast is ,cut o'` and to close when the blast is on.

9. The improvement for preventing the escape of ore dust in blast furnaces and returning it to the charge, comprising incomfbination with -the blast furnace and its air supply and twycrs, electro magnets the fields,

and they electro magnets, and a switch forv of which act upon the inner port-ion of the i tween said source of current supply and the electro magnets, and a switch for eontrollin said circuit, a bell, means connecting said bell and switch to close said switch when the bell. is lifted and open the switch when the bell is depressed. i

10. The improvement for preventing the escape of ore dust in blast furnaces and returning it to the charge, comprising inbcom-A binatiolnwith the blast furnace and it air supply and twyers, electro magnets in iers, the fields of which-act upon the inner, portion of the upper part of the blast furnace, a. source of current supply, electrical connection between said source of current supply upper part of the blast'furnace, a source of'. `current supply, electrical connection be- I and the electro magnets, and a switch for`\\105 controlling the current connection with one of saidtiers of magnets. i

11. The improvement for preventing the escape of ore dust in blast furnaces and returning it to thecharge, comprising in combination with the blast furnace and its air supply and twyers, a plurality of tiers `\o superposed. electro-magneten the fields of i which act upon' the inner portion of the lupper part of theblast furnace, a source of cui;- rent supply, electrical connections between said source of current supply andeach tier` to each tier of electro magnets, said switches being arranged to operate in a predetermined sequence. y 1

413; The improvement for preventing the' escape of ore dust in blast furnaces and re-v turningit to the charge, comprising in comhina-tion vwith the blast furnace and its air supply and twyers, a plurality of tiers of superposed electro magnets, the fields of which act upon the inner portion of the upper partof the blast furnace, a, source of curv rent supply, electrical connections between said source of current supply and each tier 'of magnets,l a switch for the circuit to each 15 tier of electro magnets, and vinterconnection between said switches -Wherebj'f one of said 'switches may be opened Without opening the. other or others of said switches.`

In'testrnony of which invention, I have 20 hereunto set my hand, atVVilmington, Dela- Ware, on this 22nd day of September, 1911.

ARTHUR J: MOXHAM.

Witnesses: M. M. HAMILTON E. E. WALL. 

